Automatic stop for elevators.



W. F. BENSON. AUTOMATIC STOP FOB- ELEVATORS.

APPLICATION FILED JAN 12, 1914.

Patented NOV. 24, 1914.

4 SHEETSSHEET 1.

m. V J -77 65 THE NORRIS PETERS CO.. FHOTO-LHHQ, WASHINGTON. D C.

W. F. BENSON.

AUTOMATIC STOP FOR ELEVATORS. APPLICATION FILED JAN.12, 1914.

1 1-1 8, 79 Patented Nov. 24, 1914.

4 SHEETS-43113111 2 o fjormqys.

IHE NORRIS PETERS 60., PHGTO-LIT!IO.. WASHING roN. D. C.

4 SHEETS-SHEET 3.

Patented Nov. 24, 1914.

W. F. BENSON.

AUTOMATIC STOP FOR ELEVATORS.

APPLICATION FILED JAN. 12, 1914.

Mafia/2nd 3 I J W 7726.

HE NORRIS PETERS ca. PHOTO-LITHO., wAsHlNcrop n c la... V VVI V EV V VM ,ll l l n 93..

w. P. BENSON, AUTOMATIC STOP FOR ELEVATORS.

APPLICATION FILED JAN.12, 1914. 1,1 18,179. Patented Nov. 24, 1914.

4 SHEETS-SHEET 4.

THE NORRIS PETERS CD. FHOTO-LITHQ, WASHINGTON. D. C.

UNITED STATES PATENT OFFICE.

WILLIAM F. BENSON, 0F BROCKTON, MASSACHUSETTS.

AUTOMATIC STOP FOR ELEVATORS.

Application filed January 12, 1914. Serial No. 811,527.

To all whom it may concern Be it known that I, VVIL'LIAM F. BENSON, acitizen of the United States, and resident of Brockton, in the county of Plymouth and State of Massachusetts, have invented, certain new and useful Improvements in Automatic Stops for Elevators, of which the following is a specification. I

The object of the invention is to provide improved mechanism for automatically stopping an elevator car orc'age in the event of any obstacle, however slight, being in the path of movement of the car or cage either up or down.

A particular object of the invention is to provide means which will with certainty be in position to act whenever the car is moving, to avoid liability of the mechanism being accidentally left out ofposition or condition for immediate action in the event of an accident being liable to occur. In other words, to employ language similar to that used in stating that a firearm is ready for instant action, it may be said that the elevator is always cocked 1 when traveling. Then, if any increase ordecrease in the apparent weight of the car or cage occurs, due to there being some obstacle such as even a hand or foot of a person, the mechanism will be certain to act instantly to stop the car.

To these ends the invention consists in the improvements which I shall now proceed to describe and claim.

Figure 1 is a side elevation, partly in section, of so much of the apparatus embodying my invention as is necessary to an understanding of the same; Fig. 2 is a sectional elevation, looking from the left of Fig. 1;

Fig. 3 is a plan view; Fig. 41 is a view simi lar to Fig. 1, but reduced in height to show more of the details on a larger scale, said figure also including the hoisting drum and, power connections; Fig. 5 is an elevation, partly in section, of the mechanism carried by the elevator car or cage, the same being on a larger scale than Fig. i; Fig. 6 is a plan view of the parts shown in Fig. 5; Fig. 7 is a detail sectional view of the parts shown at the left of Fig. 5; Fig. 8 is a detail elevation of the hoisting mechanism and the operating and controlling ropes; Fig. 9 is a detail view of the pulley-carrying yoke hereinafter described; Figs. 10 and 11 are views similar to Fig. 7, illustrating the two ropes which are guided by the yoke; Fig. 12 represents a section on line 12-12 of Fig. 5; Fig. 13 is a detail plan view of specification of Letters Patent. Patented N 0V. 1914. L

the portion of the mechanism shown at the left of Fig. 5; Figs. 14 and 15 aredetail views illustrating the operation of the double acting pawl.

Similar reference characters indicate similar parts in all the views.

A portion of the frame of the elevator car.

or cage is shown at 20, the same being vertically movable in an elevator shaft or well 21 of any suitable construction. The car or cage has a top frame 22 which supportsall of the safety or cooking mechanisms. I

The supporting cable 23 which raises and lowers the elevator car, and the control of the operation of which will be hereinafter described, has its end provided with a termmal 24 which is internallythreaded (Fig. 5) to receive the upper threaded end of a rod Said rod passes through an 'aperture in a cross web 26 of the frame 22, a setnut 27 being provided to fix the longitudinal adjustment of the terminal 2i relatively to the rod 25. The rod 25 passes down through a housing 28 secured to or integral with the 1 top frame 22, said rod having a flanged nut 29 which is held in its adjusted position by a set nut 30. A spring 31 coiled about the rod 25, and normally under compression between the top of the housing 28 and the flange of nut 29, provides for a yielding connection between the rod 25 (and consequently the supporting cable 23) and the elevator car or cage so as to permit of a slightmovement of the rod 25, which movement is yieldingly opposed in one direction by the spring 31. This slight movement is multiplied greatly by the mechanism which I will now describe.

A pair of levers 32 (Figs. 5 and 6) are i t ll rted at 33, and by means of pin pivots 3a are caused to oscillate whenever there is any movement of the rod 25 longitudinally relatively to the frame 22. The outer ends of the levers 32-are connected by links 35 to levers 36 pivoted to the frame 22 at 37 and connected by links 38 with an arm 39 pivoted at 4:0 to the frame 22. The

arm 39 is formed or provided with a toothed segment 41 which meshes with a pinion 42 secured to a shaft 43 mounted in the frame 22, said frame having a rotary cocking element or oscillatoryabutment such as a wheel 44. This wheel is. adapted to support a pendant trigger or detent 415 which is pivotally connected at 16 to one arm of a lever 4:7 pivoted a to a supporting bracket 49, a spring 50 being connected to said lever 17 and to a. relatively fixed point of the frame so as to have normal tendency to hold the lever 17 in the position shown by full lines in Fig. 5. The other end of the lever 17 has a pivoted stud 51 in which is slidingly mounted a rod 52 having a threaded upper end, an adjusting nut 53 and a set nut 5 1. The lower end of the rod 52- is connected to a pin 55 carried by a toothed disk 5t; which mounted to oscillate on a suitable studcarried by the frame 22. The rod 52 therefore is a connecting rod between the lever 47 and the toothed disk 56. The toothed portion of the disk 56 meshes with a toothed segment 57, as best shown in Fig. saidsegmcnt 57 being secured to a shafthaving an operating handle 59 (Figs. 1, and 7).

Loosely mounted on the shaft 58 is a pulley (30 for a controller cable 61 (Figs. l, 5, (3, 7, 10 and 18). Another pulley (32, beside the pulley 60, is secured to the shaft 58, said pulley 62 being for a second controller cable (53 which is preferably secured to the pulley 62 as by means of driven or screw-threaded fastenings 6 1, as illustrated in Fig. 11. The controller cable 63 is for the purpose of enabling the car to be started and stopped by a person standing on any floor of the building in which the elevator is located, the course of the cable 63 being indicated in Figs. 1, 2 and S. The mounting and operation of the cable 63 will be described hereinafter.

As best indicated in Fig. 11, a bracket arm 65 is secured to the shaft 58 so as to be oscillated with said shaft, said arm (35 being also indicated. in Figs. 5, 6 and 10. A double acting pawl 67 (see also Figs. 14- and 15) is pivotedat 68 to the arm 65, the pawl carrying a plunger 69 mounted to reciprocate in a housing 70, a spring 71 being inclosed in the housing between the inner end of the plunger and the closed end of the housing, the projecting end of the plunger contacting with the curved surface of a block 72 secured in position as by pins 73 connecting the block 72 with the frame 22. The curved surface of the block against which the plunger 69 bears is concentric with the pulley 60, and when the arm carrying the pivoted double acting pawl 67 is oscillated either by the operators manipulation of the handle 59, or by means of the automatic devices as hereinafter explained, one corner or the other of the pawl 67 will biteinto the cable 61 so as to actuate said cable in one direction or the other. This operation will best be understood by comparing Figs. 13, 1d and 15.

11 yoke 74 4, 5, 6, 7, 10, 11, 12 and 13), which moves vertically with the car as hereinafter described, carries upper and ried by a shaft 80. In order that the yoke itself may be supported so that it will move up and down with the elevator car, the up per end of said yoke has a rope 81 connected to it, said rope passing over an upper guide pulley 82, then over a guide pulley 8 1 mounted on the same shaft that which supports the upper guide pulley 83 for the supporting or raising and lowering cable 23, as best illustrated by comparing Figs. 3 and 1. The rope 81 then passes over a pulley 85 mounted on the same shaft as that which supports the pulley 86 for the cable 23. The rope 81 then passes down and around a pulley 87 mounted on the shaft 80, and to the lower end of the yoke frame 7 1.

The supporting or raising and lowering cable 23 passes from the pulley S6 to and around the winding drum 88, which is operated as hereinafter described to raise and lower the elevator car.

Referring particularly to Figs. 5 and 6, it will be seen that the pulleys 75, 7 6, are

formed or provided with disks 89 which bear against a face plate 90 carried by the elevator car 20, the entire yoke being held against lateral movement relatively to the car 20 by means of check pieces or guides 91 projecting from the car 20 past the outer faces of the disks 89. This structure permits the yoke 74 and its pulleys to have some movement relatively to the car and independently thereof, without getting out of operative position.

The cable 61 is given one or more turns or coils about a pulley 92 (Figs. 1 and 4) so that whenever the cable 61 is shifted by the operation of the shaft 58 or by the autoinatic mechanism, in one direction or the other, the pulley 92 will be oscillated to an extent preferably about one fourth or one fifth of a turn. The pulley 92 is mounted in a bracket 93 (Fig. 1), and is provided with two crank pins 9%, 95, preferably at a distance apart of about ninety degrees relatively to the axis of oscillation of the pulley. The crank pin 94: is connected by a link 96 with a bar 97 mounted in pivoted hangers 98, said bar 97 having a guide loop 99 for the belt 100 (see also Fig. 2). The belt 100 is mounted on a pulley 101 which is loose on the shaft 102 illustrated mounted in fixed pendant brackets. The shaft 102 carries a worm 103 (Figs. 3, l and 8), said Worm engaging a worm wheel 104 secured to theshaft 105 of the cable winding drum 88. The other crank pin 95 of the pulley 92 is connected by a link 106 with a bar 10'? mounted in a manner similar to the mounting of bar 97 so that it can move in the direction of its length. The bar 107 has a guide loop 109 for a crossed belt 110, said crossed belt being carried by a pulley 111 which is loose on the shaft 102. The two belts 100, 110, are carried by a driving drum 108 (Fig. 2), which is actuated or driven by any suitable power not necessary to illustrate. Fixed to the shaft 102 (Fig. 1) between the two loose pulleys 101, 111, is a pulley 112. The shaft 105 of the winding drum is mounted in bearings carried by suitable hangers indicated at 113 in Figs. 3 and l.

It will now be understood that when the disk 92 is caused to move about one quarter of a turn in the direction of the arrow (Fig. 1), the crank pin 95 will move downwardly, but this movement will not impart material longitudinal movement to the belt shifting loop carried by the bar 107, but the crank pin 9%, moving over to about the position which the pin 95 occupies in Fig. 4, will cause the bar 97 to be shifted to the right far enough so that its guide loop 99 will shift the straight belt 100 from the loose pulley 101 on to the fast pulley 112, thus causing the shaft 102 and the worm gearing to cause the drum 88 for the cable 23 to rotate in one direction. For present purposes it may be assumed that the driving drum 108 is rotated in such direction that the operation just described will cause the elevator car to be raised, the upward movement of the elevator car continuing as long as the pulley 92 and its crank pins remain in the position just described. A return movement of the pulley 92, due to shifting manipulation of the cable 61, to the point illustrated in Fig. 1, will carry the belt 100 back on to the loose pulley 101, operation of the shaft 102 instantly ceasing, and the worm gear consequently locking the cable drum 88 ig its arrested position and consequently holding the car stationary. If now the cable 61 is shifted in a direction to turn the pulley 92 in a direction the reverse of that indicated by the arrow in Fig. i, the crank pin 9 1 will move downwardly and the crank pin 95 will move over to about the position which the pin 91 occupies in Fig. 4;. This results in very slight motion being imparted to the bar 97 and the belt shifting loop 99, while the other bar 107 will be shifted sufficiently to carry the crossed belt 110 from the loose pulley 111 on to the fast pulley 112, thus causing, through the gearing described, a motion of the drum 88 in an unwinding direction to lower the elevator car. Of course, in the same manner as just described in connection with the upward travel of the car, the moment thatthe cable 61 is shifted to return the pulley 92 to the position shown in Fig. 4:, the crossed belt will be returned to the loose pulley 111, and I the drum 88, and the elevator car, will stop instantly.

The belt shifting mechanism which I have just described is eflicient and is compact. Owing to the factthat but one of the two belts is shifted any material distance at one time, theloose pulleys are comparatively narrow, that is, they do not need to be as wide as in structures which provide for the shifting of a straight and a twisted belt simultaneously equal distances.

As has been explained, the supplemental controller cable 63 is so connected with the pulley 62 on shaft 58 (Fig. 11) that any movement of the cable 63 will cause the shaft 58 to be oscillated. Of course it will be understood that when the car is moving, the cable 63 travels a distance equal to the travel of the car, but the cable 61, since it is mounted on the pulley 60, which is loose on the shaft 58, does not travel. Each of the two cables 61, 63, has a portion in the form of a loop extending inwardly from the yoke 74 and the guide pulleys ofthe latter, said loops being mounted upon the two pulleys as when the elevator car is empty, and a person on one of the floors of the building desires to cause the elevator car to move, the cable 63 can be grasped at any point of the portion which is shown at the left in Fig. 2, and said cable 63 then shifted upwardly or downwardly according to the di- If now, undersuch circumstances 1 rection of movement that the car shall take. The cable 63, being connected to the pulley 62 as shown in Fig. 11, actuates the shaft 58. Since said shaft 58 also carries the bracket arm 65, which latter carries the double acting pawl 67,. such movement of the shaft 58 will cause the arm 57 to move upwardly or downwardly. The pawl 67 being pivoted to the arm 65 may swing. If the motion of the arm 65 be downwardly, the plunger 69, dragging over the curved surface of the block 7 2, will cause the lower corner of the pawl 67 to bite into the cable 61 as illustrated in Fig. 15. This will cause the cable 61 to be shifted. Tf the movement of the arm 65 be in an upward direction, the dragging of the plunger 69 over the curved surface of the block 72 will cause the pawl 67 to swing so that its upper corner will bite the cable 61. Of course in either case, the further movement of the arm 65, after the cable 61 has been gripped, will shift said cable 61 and, through the pulley 92 and the belt shifting mechanism described, start or stop the car. The cable 63, as shown by comparing Figs. 1, 2, 3 and 4, extends over an upper pulley 114 mounted on a shaft at an angle to the shafts of pulleys 82, 86, then zillover upper and lower guide pulleys 115,

116, under another lower guide pulley 117,.

and then up to the yoke T l and over the lower guide pulley 76 thereof and to the pulley 62 as shown in Fig. 11.

I will now describe more fully the operation of the automatic safety mechanism illustrated chiefly in Fig.

Bearing in mind that all of the members or parts, excepting pulley 60, carried by the shaft are secured to that shaft, it will be understood that movement of the handle toward and to either of the dotted line positi ons shown in Fig. 5, according to whether the operator desires to go up or down, will cause the toothed segment 58 to oscillate the toothed dish either to the right or to the left. It in one direction, it will carry the crank pin to about the position indicated in Fig. l and by dotted lines in Fig. 5. it in the other direction, the crank pin would be obviously carried to about the same lowered position, excepting. that it wouldbe at the left or other side from tha-u indicated by dotted lines in llig. 5. If at this time the swinging detent 4L5 carried by lever l? is not supptnlc by the wheel 4st. this movement of the d... .16 will cause the lever t? to be shifted to the dotted line position ofliig. 5, due to the pulling down action of connecting rod 552 and the adjustable collar 53 acting upon the lever ll". The pivotal. connec tion the trigger or detent as with the levcr 4-7, in practice, is so constructed that it will not "wing too freely. In other words, as the lever t? moves from the full line position to the dotted line position of 5, the trigger or detent 44$, owing to its weight, will swii'ig to vertical position and come to rest on top of the wheel let, holding the lever 457 against the stress of spring 50. The tion of the handle 59- as explained car es the arm to swing and thereby cause the pawl 37 to p the cable 61 and operate the latte o start the car in the desired dir: ii. now the operator desires to stop the car. manipulatin of the handle 59 in a direction to cause the patwlll? to engage the cable 1 and shift the latter to stop the car the l i l will of course be returned to pcsitimi with its crank pin uppermost. This howercr will. not afllect the lever e7, because the connecting rod 52 can slide through the pivoted stud 51 of the lever. So long as there is no occasion for the action of the safety rnechanisi'm the lever all will in the position shown in Fig. l and v lines in Fig. 5. llhenever the car lu'merer moving in one direction or the other. the disk 58 must remain with its cranl: pin lowered in one direction or the other. It will now be understood. that it anything occurs to release the trigger or c tent 4.5. the spring 50 will. instantly actuate the lever 47 so as to exert a pull upon the connecting rod 52 so that the latter will return the disk 56 to the full line position shown in Figs. 5, 10 and 11. Eiuch motion of the toothed disk 56 necessarily acts through the toothed segment 57 to return the shaft to the position indicated by the full line position of the handle 59 in Fig. 5. Such motion of the shaft 58 causes the arm to swing the pawl 6? and cause the latter to actuate the cable 61 to shift the power or operating mechanism to position to stop the car.

@f course the spring 31 will be of such strength as to provide for a yielding connection. between the supporting cable and the car whether the weight on the car be great or small. In other words the spring 31 is such that there will still be some possibility of movement of the rod relatively to the car even when the car is loaded to its greatest capacity. Consequently the lever 32 may be either in the position shown by full lines in Fig. 5, when the car is running, or more or less above or below that position. according to the weight carried by the car. ll the lerer occupies a position above or below that represented in Fig. 5, the segment ll will of course also be in upwardly or downwardly swung position. it will however still be in mesh with the pinion l2, and the wheel 4A: will still be in position so that it supports the swinging trigger or detent It now any obstacle be presented. in the path of the upward or downward movement of the car, even such a slight obstacle as the projection of the foot or arm of a person. into the path of movement of the car. the contact of the car with that obstacle will be the equivalent of a slight increase or loci-ease of its weight. Any such increase or decrease causes toe lever 32 to vibrate and this, through the connections describech rotates the wheel ll su'l'hciently to oscillate the trigger or dotent so that the spring 50 will instantly actuate the lever l7 and, through the connecting rod 52, return the toothed dish 56 to the full line position of Fig. 5, thereby, as already explained, instantly and automatically stopping the car.

The spring 31 constitutes a yielding connection between the elevator car and the supporting cable so that if the effective weight of the car is varied due to the presence of some obstacle in the path of the car, the automatic p mechanism chiefly illustrated in Fig. ot the drawings is operated to instantly stop the car. The spring 50 const utes one type of motor for operating the lever l? when the latter is released. Obviously any equivalent device which would normally be in condition to actuate the lever l? when. released could be substituted for said spring. lily invention therefore includes automatic stop mechanism, a motor to actuate the same, means such as the the motor to act through the lever 47, the

connecting rod 52 and the disk 56 to arrest the car.

Having described my invention, I claim:

1. An elevator car having automatic stop mechanism including a lever, a spring connected to said lever to actuate it in one direction, a detent connected with said lever, an oscillatory abutment for said detent, and means operated by variations in the effective weight of the car for oscillating said abutment.

2. An elevator car having a lever pivoted thereto, a motor for actuating the lever in one direction, a detent for holding the lever against the power of said motor, means operated by variations in the effective weight of the car for releasing the detent, and stop mechanism connected with said lever, said stop mechanism comprising a shaft having a pulley loose thereon, acontroller cable mounted on said pulley, an arm connected to the shaft, said arm having. a double acting pawl adaptedto engage the controller cable, and connections between said lever and arm whereby movement of the lever in one direction will swing said arm.

3. An elevator car having a lever pivoted thereto, a motor for actuating the lever in one direction, a detent for holding the lever against the power of said motor, means operated by variations in the effective weight of the car for releasing the detent, and stop mechanism connected with said lever, said stop mechanism including a shaft, a pulley loosely mounted thereon, a controller cable mounted on the pulley, an arm connected to said shaft, a pawl pivotally connected with the arm, said pawl having a spring-projected plunger, a retarding surface for said plunger, and connections between said lever and arm whereby movement of the lever may be imparted to said arm.

l. An elevator car having a lever pivoted thereto, a motor for actuating the lever in one direction, a detent for holding the lever against the power of said motor, means operated. by variations in the effective weight of the car for releasing the detent, and stop mechanism connected with said lever, said stop mechanism including a shaft, a pulley loosely mounted thereon, a controller cable mounted on the pulley, an arm fixed to said shaft and having a double acting pawl adapted to engage the operating cable, a toothed segment carried by said shaft, a toothed disk engaging said segment, and a rod connecting said toothed disk and the lever.

5. An elevator car having a lever pivoted thereto, a motor for actuating the lever in one direction, a detent for holding the lever against the power of said motor, means operated by variations in the effective weight of the car for releasing the detent, and stop mechanism connected with said lever, said stop mechanism including ashaft, a pulley loosely mounted thereon, a controller cable mounted on. the pulley, an arm fined to said.

shaft and having a double acting pawl adapted to engage the operating cable, a toothed segment carried by said shaft, a toothed disk engaging said segment, and a rod having one end pivotally connected to the toothed disk, said rod having a sliding connection with the lever and provided with a stop to limit movement of the rodin one direction relatively to thelever.

6; The combination with an elevator car and a motor to actuate the same, of two independent controller cables for said motor, one of said cables having means for actuating it from a position within the car and the other being free to be actuated from a position outside of the car, said car being provided with means for automatically actuating the cable which is operative from. within the car to efiect the shifting of said cable automatically upon a variation in the effective weight of the car.

7. The combination of an elevator car having a pair of pulleys, a motor to actuate the car, independent motor controlling cables mounted on said pulleys, the cables being looped within the car, a yoke having guide pulleys for said cables, said yoke having flexible connections whereby it is caused to travel with the car, and means for preventing displacement of said yoke or frame relatively to the car.

8. An elevator car having automatic stop mechanism including a detent, and an oscillating support for said detent, means being provided whereby said support is caused to oscillate when the effective weight of the caris varied.

In testimony whereof I have aliiXed my signature, in presence of two witnesses.

WILLIAM F. BENSON. Witnesses:

OSCAR W. SMITH, EARL A. WILSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

